scholarly journals Cycle of the Seminiferous Epithelium in the Grey-headed Fruit Bat, Pteropus poliocephalus

1987 ◽  
Vol 40 (2) ◽  
pp. 203 ◽  
Author(s):  
MichaeI A McGuckin ◽  
Alan W Blackshaw
Keyword(s):  
Dna Synthesis ◽  
Meiotic Prophase ◽  
Seminiferous Epithelium ◽  
Nuclear Morphology ◽  
Fruit Bat ◽  
Pteropus Poliocephalus

The seminiferous epithelial cycle of wild P. poliocephalus could be divided into eight stages on the basis of cellular associations and nuclear morphology. The relative frequencies of the stages (1-8) were, respectively: 15'8,20'5,9'4,8'9,11'1,7'7,9'8, and 16�8%. The duration of the cycle was determined by intratesticular injection of [3Hlthymidine followed by autoradiography and estimated to be 16�0 days. The duration of meiotic prophase and spermiogenesis were both 23� 3 days. Spermatocyte DNA synthesis appeared to occur in leptotene primary spermatocytes in stage 2. The duration of spermatogenesis is similar to that in man although the organization of the cycle resembles that of rodents.

scholarly journals Correlation between DNA synthesis in the second, third and fourth generations of spermatogonia and the occurrence of apoptosis in both spermatogonia and spermatocytes

Reproduction ◽  
2003 ◽  
pp. 661-668 ◽  
Author(s):  
J Blanco-Rodriguez ◽  
C Martinez-Garcia ◽  
A Porras
Keyword(s):  
Cell Cycle ◽  
Dna Replication ◽  
Dna Synthesis ◽  
Functional Significance ◽  
Tunel Assay ◽  
Seminiferous Epithelium ◽  
Cell Cycle Checkpoints ◽  
Clear Correlation ◽  
Cellular Events ◽  
Dna Strand

In the seminiferous epithelium, both DNA synthesis and apoptosis occur at equivalent stages in various species, with apoptosis taking place mainly at the same stages as DNA replication in the second, third and fourth spermatogonial generations. As preservation of the cellular associations found at these stages may have some functional significance, it is important to determine whether there is a correlation between these cellular events. In this study, pairs of immunoperoxidase-stained adjacent testis sections from rats, mice, rabbits and cats in which either bromodeoxyuridine incorporated into the newly synthesized DNA strand (BrdU labelling) or DNA 3' end labelling of the apoptotic DNA fragments (TUNEL assay) were detected were compared. In addition, both events were analysed in double-labelled sections. These two methods revealed a clear correlation between the occurrence of DNA replication in the second to fourth generations of spermatogonia and most physiological apoptosis taking place in both spermatogonia and spermatocytes in the three different mammalian orders (Rodentia, Lagomorpha and Carnivora). This correlation may result from the synchronization of mitotic spermatogonial and meiotic spermatocyte cell cycle checkpoints operating at these stages.

Nuclear Morphology and the Ultra-Structural Localization of Deoxyribonucleic Acid Synthesis during Interphase

1969 ◽  
Vol 4 (3) ◽  
pp. 569-582
Author(s):  
GILLIAN R. MILNER
Keyword(s):  
Epithelial Cells ◽  
Dna Synthesis ◽  
Deoxyribonucleic Acid ◽  
Ultrastructural Localization ◽  
Cell Types ◽  
Acid Synthesis ◽  
Lung Fibroblasts ◽  
Nuclear Morphology ◽  
Structural Localization ◽  
Electron Microscope Autoradiography

The ultrastructural localization of deoxyribonucleic acid (DNA) synthesis was studied by electron-microscope autoradiography in human transforming lymphocytes, embryonic lung fibroblasts, epithelial cells and normoblasts. Euchromatin was found to be active in DNA synthesis in all cell types studied, whereas heterochromatin was inactive. However, DNA synthesis was also prominent in the regions where heterochromatin was thought to be decondensing to form euchromatin. Analysis of sequential changes in nuclear morphology of the transforming lymphocyte suggested that there is decondensation of heterochromatin during the S-phase until none is left. In nuclei with no heterochromatin a prominent localization of DNA synthesis was at the nuclear membrane. This sequence of complete decondensation of heterochromatin also seemed likely for fibroblasts and epithelial cells. Normoblasts however showed no stage where the nucleus was wholly euchromatic and it is suggested that in this cell decondensation of heterochromatin for replication is localized and transient.

Daytime behaviour of the grey-headed flying fox Pteropus poliocephalus Temminck (Pteropodidae: Megachiroptera) at an autumn/winter roost.

2006 ◽  
Vol 28 (1) ◽  
pp. 7 ◽  
Author(s):  
K. A. Connell ◽  
U. Munro ◽  
F. R. Torpy
Keyword(s):  
Management Strategies ◽  
Reproductive Period ◽  
Urban Environments ◽  
Flying Foxes ◽  
Fruit Bat ◽  
Open Forest ◽  
Pteropus Poliocephalus ◽  
Baseline Information ◽  
Daytime Behaviour ◽  
Flying Fox

The grey-headed flying fox (Pteropus poliocephalus Temminck) is a threatened large fruit bat endemic to Australia. It roosts in large colonies in rainforest patches, mangroves, open forest, riparian woodland and, as native habitat is reduced, increasingly in vegetation within urban environments. The general biology, ecology and behaviour of this bat remain largely unknown, which makes it difficult to effectively monitor, protect and manage this species. The current study provides baseline information on the daytime behaviour of P. poliocephalus in an autumn/winter roost in urban Sydney, Australia, between April and August 2003. The most common daytime behaviours expressed by the flying foxes were sleeping (most common), grooming, mating/courtship, and wing spreading (least common). Behaviours differed significantly between times of day and seasons (autumn and winter). Active behaviours (i.e., grooming, mating/courtship, wing spreading) occurred mainly in the morning, while sleeping predominated in the afternoon. Mating/courtship and wing spreading were significantly higher in April (reproductive period) than in winter (non-reproductive period). Grooming was the only behaviour that showed no significant variation between sample periods. These results provide important baseline data for future comparative studies on the behaviours of flying foxes from urban and ?natural? camps, and the development of management strategies for this species.

Analysis of DNA synthesis during meiotic prophase in Lilium

1971 ◽  
Vol 55 (3) ◽  
pp. 337-355 ◽  
Author(s):  
Yasuo Hotta ◽  
Herbert Stern
Keyword(s):  
Dna Synthesis ◽  
Meiotic Prophase

scholarly journals Novel strains of Klebsiella africana and Klebsiella pneumoniae in Australian Fruit Bats (Pteropus poliocephalus)

2021 ◽  
Author(s):  
Fiona K McDougall ◽  
Kelly L Wyres ◽  
Louise M Judd ◽  
Wayne S J Boardman ◽  
Kathryn E Holt ◽  
...  
Keyword(s):  
Klebsiella Pneumoniae ◽  
Resistance Genes ◽  
Multidrug Resistant ◽  
Sensu Stricto ◽  
The Public ◽  
Fruit Bat ◽  
Faecal Samples ◽  
Antimicrobial Resistance Genes ◽  
Pteropus Poliocephalus ◽  
Sequence Types

Over the past decade human associated multidrug resistant (MDR) and hypervirulent Klebsiella pneumoniae lineages have been increasingly detected in wildlife. This study investigated the occurrence of K. pneumoniae species complex (KpSC) in grey-headed flying foxes (GHFF), an Australian fruit bat. Thirty-nine KpSC isolates were cultured from 275 GHFF faecal samples (14.2%), comprising K. pneumoniae (sensu stricto) (n=30), Klebsiella africana (n=8) and Klebsiella variicola subsp. variicola (n=1). The majority (79.5%) of isolates belonged to novel sequence types (ST), including two novel K. africana STs. This is the first report of K. africana outside of Africa and in a non-human host. A minority (15.4%) of GHFF KpSC isolates shared STs with human clinical K. pneumoniae strains, of which, none belonged to MDR clonal lineages that cause frequent nosocomial outbreaks, and no isolates were characterised as hypervirulent. The occurrence of KpSC isolates carrying acquired antimicrobial resistance genes in GHFF was low (1.1%), with three K. pneumoniae isolates harbouring both fluoroquinolone and trimethoprim resistance genes. This study indicates that GHFF are not reservoirs for MDR and hypervirulent KpSC strains, but they do carry novel K. africana lineages. The health risks associated with KpSC carriage by GHFF are deemed low for the public and GHFF.

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